The Cologne Cathedral stands in the heart of that German city, near the left bank of the Rhine. This gothic cathedral was among the most revered places of worship during the Middle Ages. Cologne, declared an archdiocese by Charlemagne, received from Emperor Frederick I relics believed to be that of the Magi. The cathedral was built to accomodate the overwhelming influx of pilgrims who descended on Cologne to behold these holy relics.